will co2 injector harm fish

This is a discussion on will co2 injector harm fish within the Beginner Freshwater Aquarium forums, part of the Freshwater Fish and Aquariums category; -->
The background story to my question:
My pH is currently through the roof (not readable on my standard test strip). Every other week or ...

My pH is currently through the roof (not readable on my standard test strip). Every other week or so I lose a fish for no apparent reason. Their only sign of distress is what appears to be shyness - they hover near the bottom, hiding under plant leaves. While there is no sign of disease, fish are dying. All other water parameters are within the safe zone according to test strips. I'm assuming the problem is that my pH is too high, and some fish are just putting up with it better than others.
My tank is also heavily planted, and the plants are not growing despite having intense lighting. I would really like to get a CO2 injector to solve both my pH problem and my stunted plant growth problem. However, I can't afford a big, proper system. My budget is under $100. I found this nifty device, which looks like the yeast-in-pop-bottle contraption that I could make myself, but with some safety features added.

My pH is currently through the roof (not readable on my standard test strip). Every other week or so I lose a fish for no apparent reason. Their only sign of distress is what appears to be shyness - they hover near the bottom, hiding under plant leaves. While there is no sign of disease, fish are dying. All other water parameters are within the safe zone according to test strips. I'm assuming the problem is that my pH is too high, and some fish are just putting up with it better than others.
My tank is also heavily planted, and the plants are not growing despite having intense lighting. I would really like to get a CO2 injector to solve both my pH problem and my stunted plant growth problem. However, I can't afford a big, proper system. My budget is under $100. I found this nifty device, which looks like the yeast-in-pop-bottle contraption that I could make myself, but with some safety features added.

I would consider buying this unit if my one concern could be assuaged: will a fermentation-run injector that cannot be shut off at night cause pH fluctuations that will harm my fish?

Thanks!!
-Amy

Hi there!!! welcome to the forums!!!!!

okay so you use test strips..that has to end as of now and before you buy anything else you need to get a API master test kit. Testing strips are horribly inacurate. secondly I would like to ask you information about your tank(size, fish, did you cycle? how did you cycle? how many fish are you adding at a time? what filter? heater? declorinator? Fertilizer? what kind of light?what kind of substrate? gravel? sand? have you measured your tap water? anything in particular) if your ph is too high do not, I repeat do NOT add anything like ph regulator or anything that claimes to bring it down to normal levels because that can lead to a very unstable tank in the future and we sure dont want that. I have to recommend you a fertilizer used by experts its called Seachem's Flourish Comprehensive Supplement for the Planted Aquarium its the one most people use with heavily planted tank here. add that before you get any co2 contraptions.

here is a basic guide for cycling aguariums if you have not yet become familiar with it :)

I would also like to tell you to STAY ON TOP OF YOUR WATER CHANGES. thats super important when ever anything strange goes down in your tank do a 50% water change those always help the fish.
Also do not add any more fish! in the begining always add your fish slowly for your bacteria to adjust to the biological loads that they bring(excrement, urine, bodily fluids ect/) add three or four fish every three weeks or so. also the light the experts recommend a "daylight" tube with a kelvin rating between 6000K and 7000K just a heads-up

I have helped you the best way I can there are many people here that can give you additional advice and have far superior knowledge than I have. I am so happy that you joined our community its always for the sake of the fish AND again if you have any questions at all just ask.

ANYTHING that you might have in mind ask it could make a big difference in the health and well-being of your little fishies!!!!

Thanks for all the advice!
My tank is 75 gallons. It used to be a cichlid tank, but I sold all the cichlids and started adding community fish (made the transition about 6 months ago). When I add fish it's a few at a time, maybe 3 a month maximum. I don't plan to add any more fish now.
The tank cycled, and it had been stable for a couple of years. The chemistry started to get wonky when I made the mistake of turning it into a planted tank with insufficient lighting. As plants died, my amonia spiked. I fixed this problem with frequent water changes, an amonia neutralizing filter cartridge, and new T5 HO lights. I now have 2.5Watts/gallon. I have 2 fluorescent grow bulbs, one actinic lamp (that came free with my fixture), and one 10000K lamp.
My filter is an aquaclear 110 (which I wish I could afford to replace because it's 11 years old and noisy even with a new impeller). Aquaclear heater as well.
I do not currently use a fertilizer, but I will make a trip to the store soon for Seachem's Flourish Comprehensive Supplement .
I have a medium coarseness gravel substrate. My tap water is the same as my aquarium water using the test strips. I'm wishing I hadn't payed so much more for the test strips if they're so inaccurate.
I had already decided not to add a chemical pH adjuster, because my GH and KH are pretty high, so I figured I'd have trouble breaking through the buffers with anything but CO2 injection.

Since I got my new T5 lights I've had an expected algae bloom. I just adjusted the lights to be on for 4 hours, off for 3, and on for 4. I heard somewhere that that stints algae growth... Also to try to stay on top of the algae I've been doing 25% water changes weekly.
The fish deaths started after I got the new lights as well. But I don't know what lethal effects bright lights could cause.

Also, I have another symptom to add, besides the fact that they hover near the bottom for a day or two before death. One of my sad looking fish has a nipped tail. This could be the work of the halfbeaks, or perhaps fin rot...?? Although there are no signs of parasites.
Also, the other sad looking fish has started swimming in circles, kind of on an angle, as if one half of its body has been paralized. It doesn't look like a swim-bladder problem that I've ever seen before... something about it is different... very strange... almost like it's confused...

As for my CO2 harming fish question, I am starting to think that the risk of nighttime CO2 spikes with a DIY-style injector is too much of a risk. I'll start shopping around for a real system.

I have a couple of those Hagen systems on my 80 gallon tank. I don't aerate at night, but it doesn't seem to bother my discus. At first I thought dropping in an airstone every night would be necessary, but the oxygen apparently doesn't drop low enough to bother them. Plus they sleep at night anyways, so they're less active and breathe more slowly.

When researching the CO2 option I read that changes in PH aren't what shocks the fish; changes in hardness are. This coincides perfectly with my experiences, as I lost fish after the hardness of our water suddenly changed but have never seen them bothered by just a pH change. Have you tested your water's hardness? If that's off the charts as well then that may be your problem. In that case CO2 won't help anyways, to my knowledge. You'll need a reverse osmosis unit to filter most of the water you use for changes, mixing it with tap water or adding a supplement to replenish the minerals that it removes. The good news is that those are way cheaper than a CO2 injection system.

Hopefully that's somewhat helpful. I'm by no means an expert on CO2 and chemistry, but that's just what I've come across while doing my own research. Also, just FYI... this is in the saltwater section. You'd probably get more replies in one of the freshwater sections.

Thanks for all the advice!
My tank is 75 gallons. It used to be a cichlid tank, but I sold all the cichlids and started adding community fish (made the transition about 6 months ago). When I add fish it's a few at a time, maybe 3 a month maximum. I don't plan to add any more fish now.
The tank cycled, and it had been stable for a couple of years. The chemistry started to get wonky when I made the mistake of turning it into a planted tank with insufficient lighting. As plants died, my amonia spiked. I fixed this problem with frequent water changes, an amonia neutralizing filter cartridge, and new T5 HO lights. I now have 2.5Watts/gallon. I have 2 fluorescent grow bulbs, one actinic lamp (that came free with my fixture), and one 10000K lamp.
My filter is an aquaclear 110 (which I wish I could afford to replace because it's 11 years old and noisy even with a new impeller). Aquaclear heater as well.
I do not currently use a fertilizer, but I will make a trip to the store soon for Seachem's Flourish Comprehensive Supplement .
I have a medium coarseness gravel substrate. My tap water is the same as my aquarium water using the test strips. I'm wishing I hadn't payed so much more for the test strips if they're so inaccurate.
I had already decided not to add a chemical pH adjuster, because my GH and KH are pretty high, so I figured I'd have trouble breaking through the buffers with anything but CO2 injection.

Since I got my new T5 lights I've had an expected algae bloom. I just adjusted the lights to be on for 4 hours, off for 3, and on for 4. I heard somewhere that that stints algae growth... Also to try to stay on top of the algae I've been doing 25% water changes weekly.
The fish deaths started after I got the new lights as well. But I don't know what lethal effects bright lights could cause.

Also, I have another symptom to add, besides the fact that they hover near the bottom for a day or two before death. One of my sad looking fish has a nipped tail. This could be the work of the halfbeaks, or perhaps fin rot...?? Although there are no signs of parasites.
Also, the other sad looking fish has started swimming in circles, kind of on an angle, as if one half of its body has been paralized. It doesn't look like a swim-bladder problem that I've ever seen before... something about it is different... very strange... almost like it's confused...

As for my CO2 harming fish question, I am starting to think that the risk of nighttime CO2 spikes with a DIY-style injector is too much of a risk. I'll start shopping around for a real system.

Thanks for the help and the warm welcome!
-Amy

gosh okay..I would definitely get a new filter, prefibly a Eheim for 80 gallon aquariums. if your heater is old too change it. dont forget some air stones.

I too have over spent on testing strips but really get that API master test kit before you get anything else. I think your 10000K is a bit strong but Im not too sure. knowing the hardness of the water could be critical in your situation like ostara said...

gosh I wish I could diagnose the problem you know but this is a just bit much for my experience level...

Welcome to Tropical Fish Keeping forum Amy; glad you found us and joined.

Your plant problem first is easily solved. Nutrients. Plants need "food" which are nutrients, 17 of them, and this must be sufficient to balance the light. [You have a lot of light, too much in my opinion, more on that in a moment.] Without nutrients, light will not allow plants to grow, and algae will take advantage. Your "siesta" method is probably what has kept algae at bay, or you would have a mess with all that light and little if any nutrients. The suggestion for Seachem's Flourish Comprehensive Supplement for the Planted Aquarium is well made. They make several products in the Flourish line, make sure it is the Comprehensive. Once or twice a week and your plants should be better.

Now the light. This is a 75g, presumably 4 feet in length? Are the two T5 fluorescent tubes full length, i.e., 48-inch tubes? When I know these answers, I can probably suggest something to help here.

I myself would not bother with the added expense and issues with CO2, unless you have a desire for fast plant growth. In a low-tech or natural system, plants grow well but more slowly, but the benefits are still all there. The photos of my tanks under "Aquariums" below my name on the left are of tanks using minimal light, with nutrients (Flourish Comprehensive) in balance. No CO2.

Now to the fish problem. This could be due to the light, but not likely; however, having tried T5 HO light myself, I found it far too bright for the fish (and me). Floating plants are helpful to shade the light. But it is more likely something else or a combination. One thing we need to know are numbers: "high" pH, hardness, ammonia really tells us very little. Can you give us the numbers for the pH and hardness, both of your tap water and tank water? Tap water numbers you should be able to get from the water supply people, many have websites, or if not they can tell you. This will tell us more.

Your tank has way to much light on it. A agree though that first step is you need a API master test kit. I would also cut your light in half. I am assuming your fixture has two power switches and 4 bulbs. Turn off half of the bulbs.

Anyway on to CO2, a yeast-style reactor can IMO do zero harm on a 75 gallon. These systems DIY or premade are not meant for large tanks or to raise the CO2 levels very high at all. They simply do not have the output to cause any spike at day or night in a 75gallon even if you wanted it too. You would need a pressurized system before you need to worry about accidental overdose or spikes, but lots of people leave these running for 24/7 as well without problems. Pressurized systems though run much higher then the budget you first mentioned, but more importantly then any of this is that CO2 would be ineffective and basically a waste on your tank as it is now.

Your filter is a HOB style filter and its surface disruption will actively remove CO2 from the water. Also I agree that your tank needs a better filter if you intend to really go planted. As someone mentioned a canister would be good, but they are pricey. Do not add any air stones though... these have the same negative effects as your HOB filter does in terms of a planted aquarium.

CO2 will not solve your problems. There are a few general ways to make a planted tank, low-tech, high-tech, and El Natural. Right now you have lighting way into high-tech levels and everything else is on par with low tech. If you intend to use all that lighting not only do you need pressurized CO2 you need heavy fertilization on par with the Estimative Index or one of the other high nutrient regimes. These BTW are not done with store bought fertilizers... You may find that a enriched substrate would be very beneficial too. Take note though, that this is the harder method. It is targeted towards high light plants and lots of growth. Daily fertilizing and 50% weekly water changes are required initially.

Also if your pH is high(IDK how high really... "through the roof" is not very informative) CO2 will not really drop it THAT much. I run pressurized systems and if I were to max out CO2 as much as I could without harming the fish I might get mine to drop a whole degree. This though depends entirely on your water....

I agree with byron that we really need to know water stats with a good test kit before we can do anything but speculate on what the problem might be...

A quick update on what I've done so far:
I started on liquid fert, although my crummly little pet store in my town doesn't carry Seachem's. I'm using liquid CO2 for now until I can get to the nearest Big Al's which is in a different city.
I've cut down on my light by unscrewing one of my regular 40W fluorescent grow bulbs. This leaves me with 1 40W fluorescent grow bulb, one 10000K (56W) T5 bulb, and one actinic bulb. I read somewhere that some people have reported an algae bloom when using actinic bulbs over freshwater. As soon as I have the money I'll replace it with a regular T5 bulb (can't run the fixture without two bulbs...). Would my plants get enough light with 2 10000K 56W bulbs? If so, I'll eventually just remove my standard fluorescent fixture entirely.
I figure I might as well wait on giving numbers until I get a proper test kit.

Little by little I'll fix the problems.
I'm also putting my CO2 injector idea on hold. Maybe when I get the tank stable and balanced again my plants will start to flourish without CO2.

As both Mikaila and I previously said, CO2 is not going to solve the problems. I still say, don't use the Excel or whatever "liquid carbon" you have. The other nutrients are not there, and plants cannot manage without everything.

Plants will photosynthesize (= grow) if everything they need is present: adequate light and all 17 nutrients. As soon as one of these is no longer available, photosynthesis slows or stops completely (depends upon what the missing item is). It is called the law of minimum, or limiting factor to photosynthesis. Adding more light, or more iron, or more CO2 when something else that is essential is lacking will only contribute to more algae because algae can take advantage of all this.

Actinic light is not good plant light, and again algae can use it (as in marine setups too) and will.